CN102144300A

CN102144300A - Fabrication method for a solar cell

Info

Publication number: CN102144300A
Application number: CN2009801348796A
Authority: CN
Inventors: 山室和弘; 汤山纯平; 宋一兵; 青柳秀胜
Original assignee: Ulvac Inc
Current assignee: Ulvac Inc
Priority date: 2008-09-22
Filing date: 2009-09-17
Publication date: 2011-08-03
Anticipated expiration: 2029-09-17
Also published as: EP2337086A1; US20110171757A1; JPWO2010032465A1; JP5048843B2; WO2010032465A1; CN102144300B; TW201015741A

Abstract

Disclosed is a fabrication method for a solar cell that comprises a substrate and a structural body in which a first conductor layer, a photovoltaic conversion layer, and a second conductor layer are sequentially laminated on this substrate, said structural body consisting of a plurality of block elements that are electrically segregated by a specified size, and wherein adjacent block elements are electrically connected. The method is provided with a defect region specifying step, in which regions where structural defects are present are specified from the plurality of block elements, and a refurbishing step, in which a laser beam is irradiated in the regions or the perimeter thereof to remove the structural defects. The refurbishing step comprises a step (a), in which the structural body is irradiated by a first laser to remove or isolate the region, and a step (beta), in which the edges of the structural body produced by the removal or isolation are irradiated by a second laser to clean the edges. A laser consisting of the first laser defocused so that the focal position thereof is separated from the substrate is used as the second laser.

Description

The manufacture method of solar cell

Technical field

The present invention relates to the manufacture method of solar cell, more specifically, relate to a kind of deterioration in characteristics that can not cause in the thin-film solar cells, and repair the technology of the fault of construction that in this thin-film solar cells, produces.

The application is willing to advocate priority 2008-242541 number based on 09 22nd, 2008 spies in Japanese publication, quotes its content at this.

Background technology

From effectively utilizing viewpoint of energy, in recent years, solar cell just more and more extensively and is at large utilized.Particularly utilize the solar cell of silicon single crystal, the energy conversion efficiency excellence of per unit area.In utilizing the solar cell of this silicon single crystal, use the silicon chip that the cutting of silicon single crystal ingot is obtained.In order to make this ingot, need wasteful energy, so its manufacturing cost height.Particularly, if want to utilize silicon single crystal to be implemented in the outdoor large-area solar cell that is provided with that waits, be quite to spend manufacturing cost at present just.Therefore, utilized the solar cell of amorphous (noncrystalline) silicon thin film that can more cheap manufacturing, popularized as solar cell cheaply.

Non-crystal silicon solar cell is by receiving that amorphous silicon film (i type) that the light time produces electronics and hole is clamped by the silicon fiml of p type and n type and the semiconductor film of the layer structure that is called as the pin knot that form and the electrode formation that forms respectively on two faces of this semiconductor film.

The electronics and the hole that produce based on sunlight, mobile actively because of the potential difference of p type and n N-type semiconductor N, by repeating this moving continuously, on the electrode of two faces of semiconductor film, produce potential difference.

This non-crystal silicon solar cell is for example made by the following method.At first, form transparent conductive oxide transparency electrodes such as (TCO, Transparent Conducting Oxide) on as the glass substrate of sensitive surface side and be used as first conductive layer with light transmission.Then, on this first conductive layer, form the semiconductor film constitute by amorphous silicon and be used as photoelectric conversion layer, and then on this photoelectric conversion layer, form as the Ag film of backplate etc. and be used as second conductive layer.In the non-crystal silicon solar cell that comprises the structure that constitutes by above-mentioned first conductive layer, photoelectric conversion layer and second conductive layer, there are the following problems, if promptly just on substrate, equably each layer carried out film forming, will cause the little problem of the potential difference of two faces of semiconductor film and the problem of their resistance value with large tracts of land.Therefore, in non-crystal silicon solar cell, for example, structure according to each given size on electric by subregion and form a plurality of zoning units, be electrically connected between the zoning unit adjacent one another are.Particularly, be made as following structure: by the structure that evenly forms with large tracts of land is used laser etc. on substrate, formation is called as the groove of score line (ス Network ラィ Block ラィ Application), is used as a plurality of thin OBL zoning units, is electrically connected these zoning units with series system.

The non-crystal silicon solar cell of known said structure can produce some faults of construction in its fabrication stage.For example, when forming amorphous silicon film, in this amorphous silicon film, sneak into particle sometimes or produce pore.Because these faults of construction cause first conductive layer (transparency electrode) and second conductive layer (backplate) partial short-circuit sometimes.In addition, on substrate, form after the structure, when being divided into a plurality of zoning unit by score line, the metal film that second conductive layer also can occur forming is along this score line fusing and arrive first conductive layer, causes the situation of first conductive layer and the second conductive layer partial short-circuit.

So, if in structure, produce fault of construction, such as partial short-circuit between first conductive layer on two faces that are configured in photoelectric conversion layer (semiconductor film) respectively and second conductive layer, then can produce the problem that generating voltage descends and the generating efficiency reduction is such of non-crystal silicon solar cell.Therefore, in the manufacturing process of existing non-crystal silicon solar cell,, come the reparation problem by the fault of construction that causes this short circuit etc. is detected and remove the position that produces this fault of construction.

For the position and the structure that produce this fault of construction are insulated to repair, for example, as described in patent documentation 1, to this position irradiating laser, so that produce the position insulation of fault of construction.At this moment, as shown in figure 15, form and removed photoelectric conversion layer and this two-layer repair track of second conductive layer (R1～R4) thereby shine a kind of laser L from substrate-side.This repair track (R1～R4) form in the mode of crossing (crossing) score line 119 (119a, 119b), thus remove or separated fault of construction A.

But when crossing score line 119 (119a, 119b) that (crossing) conduct first conductive layer and second conductive layer when carrying out the removal of fault of construction A, the insulation effect that produces the region D of fault of construction A weakens, and is difficult to positively make this region D insulation.

Therefore,, for example, need to use, remove first conductive layer 113, photoelectric conversion layer 114 and second conductive layer 115 these three layers (with reference to figure 16A, 16B) as patent documentation 2 disclosed technology in order positively to make this region D insulation.

In addition, when the reason of fault of construction is first conductive layer 113,, also have to, the photoelectric conversion layer 114 and second conductive layer 115 are also together removed with first conductive layer 113 in order to repair this fault of construction.

But, shown in Figure 16 A, when by irradiating laser L to first conductive layer 113 that constitutes structure 112, photoelectric conversion layer 114 and second conductive layer 115 these three layers when once removing operation, shown in Figure 16 B, the part of first conductive layer 113 that evaporates because of irradiating laser L is sometimes as on the end 112a of residue attached to the photoelectric conversion layer 114 of the structure 112 that is formed with repair track R and second conductive layer 115.And, owing on the end 112a of a part attached to the photoelectric conversion layer 114 and second conductive layer 115 of first conductive layer 113 of this evaporation, therefore might become new fault of construction, thereby cause the deterioration of characteristic of solar cell.

Patent documentation 1: Japanese kokai publication sho 59-99467 communique

Patent documentation 2: TOHKEMY 2008-66453 communique

Summary of the invention

In view of this, the object of the present invention is to provide a kind of manufacture method of solar cell, in order to repair the fault of construction of first conductive layer and the second conductive layer partial short-circuit, and need pass through irradiating laser, with first conductive layer, when photoelectric conversion layer and second conductive layer are also together removed, can alleviate the deterioration of the characteristic in the solar cell.

(1) manufacture method of solar cell of the present invention, described solar cell have substrate and on this substrate with the overlapping successively structure that forms of first conductive layer, photoelectric conversion layer and second conductive layer, this structure is formed a plurality of zoning units by subregion according to each given size on electric, be electrically connected between the described zoning unit adjacent one another are, the manufacture method of described solar cell comprises: defect area is determined operation, determines the zone that has fault of construction from described a plurality of zoning units; And reparing process, to described zone or its circumfusion laser beam, removing described fault of construction, described reparing process comprises: operation α, described structure is shone first laser, remove or separate described zone; And operation β, second laser is shone in end to the described structure that produces because of described removal or separation, remove described end, described second laser uses and described first laser is defocused so that the laser that the focal position of described first laser obtains after away from described substrate.

(2) in the manufacture method of above-mentioned (1) described solar cell, also can be in described operation β, move the irradiation position of described second laser along the in-plane of described substrate, described second laser is shone in the end of the described structure that do not have described that side of fault of construction.

(3) in the manufacture method of above-mentioned (2) described solar cell, also can be in described operation β, replace described second laser of irradiation and shine the 3rd laser, the frequency of the laser beam of described the 3rd laser is different with described first laser, and described the 3rd laser defocused so that the focal position of described the 3rd laser than described first laser more away from described substrate.

(4) in the manufacture method of above-mentioned (1) or (2) described solar cell, also can be before described operation α shines described first laser, further have and described structure is shone the 4th laser and form the operation of slot part, described the 4th laser for being defocused so that its focal position than described first laser more away from the laser of described substrate, after forming described slot part, the described slot part of described structure is shone described first laser.

In the manufacture method of above-mentioned (1) described solar cell, structure is shone first laser, remove first conductive layer, photoelectric conversion layer and second conductive layer and remove or separate the zone that has fault of construction for these three layers.Then, to shining second laser because of the end of shining the structure that this first laser forms, described second laser is that first laser is defocused so that the focal position of first laser obtains after away from substrate.Defocus by this, form the condition that second laser can only be removed the photoelectric conversion layer and second conductive layer.Therefore, be removed by shining this second laser in the last new fault of construction (by shining adhering to of removed first conductive layer of first laser) that produces of the wall (end) of photoelectric conversion layer because of shining first laser, therefore the end that can remove structure.

Therefore, even in order to repair the fault of construction of first conductive layer and the second conductive layer partial short-circuit, and need, with first conductive layer by irradiating laser, when photoelectric conversion layer and second conductive layer are also together removed, also can alleviate the deterioration of the characteristic in the solar cell.

Description of drawings

Fig. 1 is the amplification stereogram of major part that an example of the solar cell that the manufacture method of utilizing solar cell of the present invention makes is shown.

Fig. 2 is the cutaway view of an example that the layer structure of solar cell shown in Figure 1 is shown.

Fig. 3 is the flow chart of summary that the manufacture method of solar cell involved in the present invention is shown.

Fig. 4 is the cutaway view of solar cell that the existence example of fault of construction is shown.

Fig. 5 illustrates the key diagram that defect area is determined the situation of operation.

Fig. 6 A is the figure that first example of defect repair operation involved in the present invention is shown.

Fig. 6 B is the figure of example that the defect repair operation of Fig. 6 A is shown.

Fig. 6 C is the figure of example that the defect repair operation of Fig. 6 A is shown.

Fig. 6 D is the figure of example that the defect repair operation of Fig. 6 A is shown.

Fig. 7 A is the figure that second example of defect repair operation involved in the present invention is shown.

Fig. 7 B is the figure of example that the defect repair operation of Fig. 7 A is shown.

Fig. 7 C is the figure of example that the defect repair operation of Fig. 7 A is shown.

Fig. 8 A is the follow-up figure that the defect repair operation shown in Fig. 7 A～7C is shown.

Fig. 8 B is the follow-up figure that the defect repair operation shown in Fig. 7 A～7C is shown.

Fig. 9 A is the figure that the 3rd example of defect repair operation involved in the present invention is shown.

Fig. 9 B is the figure of example that the defect repair operation of Fig. 9 A is shown.

Fig. 9 C is the figure of example that the defect repair operation of Fig. 9 A is shown.

Figure 10 A is the follow-up figure that the defect repair operation shown in Fig. 9 A～9C is shown.

Figure 10 B is the follow-up figure that the defect repair operation shown in Fig. 9 A～9C is shown.

Figure 10 C is the follow-up figure that the defect repair operation shown in Fig. 9 A～9C is shown.

Figure 11 A is the figure that the 4th example of defect repair operation involved in the present invention is shown.

Figure 11 B is the figure of example that the defect repair operation of Figure 11 A is shown.

Figure 11 C is the figure of example that the defect repair operation of Figure 11 A is shown.

Figure 12 A is the follow-up figure that the defect repair operation shown in Figure 11 A～11C is shown.

Figure 12 B is the follow-up figure that the defect repair operation shown in Figure 11 A～11C is shown.

Figure 13 A is the figure that the 5th example of defect repair operation involved in the present invention is shown.

Figure 13 B is the figure of example that the defect repair operation of Figure 13 A is shown.

Figure 13 C is the figure of example that the defect repair operation of Figure 13 A is shown.

Figure 14 A is the follow-up figure that the defect repair operation shown in Figure 13 A～13C is shown.

Figure 14 B is the follow-up figure that the defect repair operation shown in Figure 13 A～13C is shown.

Figure 14 C is the follow-up figure that the defect repair operation shown in Figure 13 A～13C is shown.

Figure 15 is the figure that an example of existing defect repair operation is shown.

Figure 16 A is the figure that another example of existing defect repair operation is shown.

Figure 16 B is the figure of example that the defect repair operation of Figure 16 A is shown.

Embodiment

Below, be example with the situation of amorphous silicon type solar cell, describe based on the execution mode of accompanying drawing the manufacture method of solar cell involved in the present invention.

Fig. 1 is the amplification stereogram of major part that an example of the amorphous silicon type solar cell that the manufacture method of utilizing solar cell involved in the present invention makes is shown.In addition, Fig. 2 is the cutaway view that the layer structure of solar cell shown in Figure 1 is shown.

Solar cell 10 shown in Figure 1 has: have the insulating properties substrate 11 of light transmission and be formed on structure 12 on the face 11a of this substrate 11.

Substrate 11 is made of insulating material excellent such as the transmittance of sunlights such as glass or transparent resin and that have a durability.In this solar cell 10, inject sunlight S from another face 11b side of this substrate 11.

Structure 12 comprises: first conductive layer (transparency electrode) 13, photoelectric conversion layer 14 and second conductive layer (backplate) 15 with light transmission.That is,, thereby form structure 12 by first conductive layer 13, photoelectric conversion layer 14 and second conductive layer 15 is overlapping successively.

First conductive layer 13 serve as reasons have light transmission metal oxide such as zinc oxide aluminum (AZO, added the ZnO of Al (aluminium)), zinc-gallium oxide (GZO, added the ZnO of Ga (gallium)), the TCO electrode that constitutes of tin indium oxide TCO such as (ITO, Indium Tin Oxide).

Shown in the top of Fig. 2, photoelectric conversion layer 14 for example is made of p type amorphous silicon film 17, n type amorphous silicon film 18 and the i type amorphous silicon film 16 that clips between above-mentioned p type amorphous silicon film 17 and n type amorphous silicon film 18, forms pin structure or nip structure.The thickness of this photoelectric conversion layer 14 for example can be made as 2～300 nanometers (nm).

In addition, photoelectric conversion layer 14 also can be for lamination on the pin of amorphous silicon structure or nip structure the pin structure of microcrystal silicon or the laminated construction of nip structure.

Sunlight by the substrate 11 and first conductive layer 13 is injected into this photoelectric conversion layer 14, when the energy particle in being included in sunlight strikes i type amorphous silicon film 16, owing to photovoltaic effect produces electronics and hole.Like this, because of the potential difference between p type amorphous silicon film 17 and the n type amorphous silicon film 18, electronics moves towards n type amorphous silicon film 18, and move towards p type amorphous silicon film 17 in the hole.This mobile by repeating continuously actively, thus between first conductive layer 13 and second conductive layer 15, produce potential difference.By taking out these electronics and holes from first conductive layer 13 and second conductive layer 15 respectively, thereby can with transform light energy electric energy (opto-electronic conversion).

Second conductive layer 15 can be made of Ag (silver) or Cu conductive metal films such as (copper).The thickness of this second conductive layer 15 for example can be made as 2～300nm.

In addition, second conductive layer 15 also can be made as the laminar structure of TCO and metal or alloy.TCO for example is AZO, GZO or ITO etc.Metal or alloy for example is Ag or Ag alloy (Ag that for example contains Sn (tin) and Au (gold)).

By be formed on second conductive layer 15 with and the photoelectric conversion layer 14 of lower floor on score line 19, structure 12 for example is divided into that profile is thin OBL a plurality of

zoning units

21,21.......These

zoning units

21,21...... each other on electric by subregion, and between zoning unit adjacent one another are 21, for example be electrically connected with series system.In view of the above, the potential difference in this structure 12 increases, and can obtain more electric current.

Score line 19 can be by after for example being formed uniformly structure 12 on a face of substrate 11, utilizes removal second conductive layer 15 and photoelectric conversion layers 14 such as laser, and forms with predetermined distance formation groove on structure 12.

Preferably, constituting on second conductive layer 15 of structure 12, further forming the protective layer (not shown) that constitutes by insulative resin etc.

Below, to as the manufacture method of the solar cell of above-mentioned structure describe.

Fig. 3 is the flow chart that stage illustrates the manufacture method of solar cell of the present invention.Wherein, special in the operation that detects reparation from fault of construction, be elaborated.

At first, as shown in Figure 1, (structure forms operation: P1) to form structure 12 on a face 11a of transparency carrier 11.Structure 12 for example can begin order lamination first conductive layer 13, the photoelectric conversion layer 14 and second conductive layer 15 and forms from substrate 11 sides.

As shown in Figure 4, in the process that forms this structure 12, be created in the fault of construction A1 that sneaks into pollution in the photoelectric conversion layer 14, the problems such as fault of construction A2 that in photoelectric conversion layer 14, produce small pore sometimes.This type of fault of construction A (A1, A2) makes partial short-circuit (electric leakage) between first conductive layer 13 and second conductive layer 15, has reduced the generating efficiency of solar cell 10.

Then,, form score line 19 to structure 12 irradiating laser etc. for example, as shown in Figure 1, with structure 12 be divided into thin OBL a plurality of zoning units 21, (zoning unit forms operation to 21......: P2).

The solar cell 10 that forms through operation as implied above is then being determined operation (P3) and defect repair operation (P4) afterwards through defect area, forms (P5) such as protective layers, thereby is accomplished.

Determine in the operation (P3) at defect area, determine the zone (defect area D) that exists in each zoning unit by the fault of construction of above-mentioned A1～A2 representative.

In defect repair operation (P4), removal or separation are determined the zone that has defective that operation is detected by this defect area, thereby repair zoning unit (structure).

Below, such defect area is determined the concrete example of operation and defect repair operation describes.

＜defect area is determined operation 〉

Determine operation as defect area, just do not limit especially as long as can determine rejected region, for example can enumerate measurement, the curve factor (FF, fill factor) of resistance value measurement, utilize the shooting of ccd video camera etc. etc.

As shown in Figure 5, for example, when zoning unit 21s that determines to exist fault of construction by the measurement of resistance value and defect area D, set several measurement points, measured resistance value between zoning unit adjacent one another are 21,21 along the length direction L of thin OBL zoning unit 21.Since defect area D and near resistance value descend, therefore observe by distribution (decline of resistance value) to this measured value, can determine the zoning unit 21s and the defect area D that there are fault of construction.In addition, in Fig. 5, the part of representing with the circle of blacking illustrates the decline of resistance value, when having fault of construction in zoning unit 21s, to defect area D and near when measuring, the measurement (ゲ one ジ) in this zoning unit 21s left side illustrates the decline of resistance value.

At this moment, also can use the measurement mechanism that is spaced a plurality of probes along the length direction L of zoning unit 21 in accordance with regulations, once move up and down the measurement of finishing the resistance value between the zoning unit 21 by probe.Perhaps also can adopt probe is scanned along the length direction L of zoning unit 21, carry out method that moving up and down of probe measure etc. repeatedly at the measurement point of regulation.

This defect area determines that the mensuration of the resistance value in the operation also can adopt following any one mode: two probe-types that the bias voltage that utilization will apply setting carries out with measuring the two one group of two probes of holding a concurrent post of current value or make the bias current that applies regulation and four point probe formula that the measuring voltage value uses respectively that different probes carries out is made of two groups of four probes.Based on above-mentioned magnitude of voltage and current value, calculate each resistance value.

In addition,, also can determine the threshold value of a plurality of resistance values, change the measurement interval of terminal by each threshold value as other detection method.For example, set threshold X, Y, Z (but the X＞Y＞Z), use the measurement mechanism that is spaced a plurality of probes along the length direction L of zoning unit 21 in accordance with regulations, measured resistance value between zoning unit adjacent one another are 21,21 of resistance value.When the resistance value that measures is threshold X when above, utilize the probe that separates the position of 10 probe separation with this measuring point, measure next resistance value.More than the resistance value that measures becomes threshold value Y and threshold X when following, utilize the probe that separates the position of 5 probe separation with this measuring point, measure next resistance value.More than the resistance value that measures becomes threshold value Z and threshold value Y when following, utilize the probe that separates the position of 2 probe separation with this measuring point, measure next resistance value.When the resistance value that measures becomes threshold value Z when following, utilize each probe measurement resistance value.When measured value increases, on the contrary, when surpassing threshold value, measure with regard to enlarging to measure at interval.When having defective, because the resistance value that measures changes (declines) lentamente, therefore measure the interval by changing according to each threshold value like this, just can be rapidly and detect defective locations exactly.

Determine operation similarly based on the defect area that FF measures, the FF value between the zoning unit adjacent one another are is compared, thereby the FF value zone of reduction especially can be defined as existing the zone of fault of construction.

Determine for example to use the ccd video camera that made up high-rate lens to carry out based on the defect area of the shooting of ccd video camera.In order to come the position of fault of construction is judged according to the image that photographs, can judge based on visual by the people, also can utilize computer in addition, compare by view data and judge the view data of the zoning unit of detected object and the zoning unit that does not have defective that photographs in advance.

Determine operation through defect area as implied above, found to exist the solar cell in the zone of fault of construction to be sent to the defect repair operation that the following describes.On the other hand, the solar cell of zoning unit of finding to exist fault of construction is then directly as non-defective unit, forms operation P6 etc. through protective layer and becomes product.

In addition, determine operation, can determine the position that has fault of construction in more detail by repeatedly carrying out above-mentioned defect area.At this moment, preferably, the measurement of resistance value is measured at interval at interval thinlyyer than the measurement of the resistance value in the operation of front.

In addition, to the measurement of the measurement of resistance value, FF, utilize the shooting of ccd video camera to make up, also can determine defect area.At first, carry out the distribution of resistance value and/or the measurement of FF and determine the zone that has fault of construction.Then, take the zone that this is circled, thereby can in zoning unit 21, determine the accurate position that has fault of construction with accurate location by utilizing image taking unit such as ccd video camera.

Defect area based on shooting is determined operation, when checked property has large tracts of land, needs for a long time.Therefore, in advance iris out the zone that there be fault of construction by the distribution of measurable resistance value at short notice this moment, only this zone of small size carried out determining operation based on the defect area of shooting afterwards.In view of the above, even when checked property has large tracts of land, also can promptly determine the accurate position of fault of construction in the short time at the utmost point.

＜defect repair operation 〉

Determine the accurate position of fault of construction in zoning unit 21 after, then the fault of construction A (A1, A2) to solar cell repairs (defect repair operation: P4).In this defect repair operation, the region D irradiating laser of determining determining operation that has fault of construction A through above-mentioned defect area, there be first conductive layer 13, photoelectric conversion layer 14 and second conductive layer 15 of the region D of this fault of construction A in removal.And then, remove and remove the new fault of construction (being attached to first conductive layer of the wall (end) of photoelectric conversion layer 14) that first conductive layer produces because of shining this laser.

That is, the reparation of fault of construction A (A1, A2) comprises: operation α, structure 12 is shone first laser repeatedly, and remove or be separated in defect area and determine the region D that has fault of construction determined in the operation; And operation β, the end of the structure 12 that produces because of this operation α is shone second laser repeatedly, remove the end of structure 12, described second laser is that first laser is defocused so that the focal position of first laser obtains after away from substrate 11.

In this defect repair operation,, therefore can only remove the structure 12 of the Min. scope that comprises fault of construction A owing to determine to have determined in the operation the accurate position of fault of construction A in zoning unit 21 at defect area.And then, can remove, so that remove because of removing the new fault of construction that fault of construction A produces.

This defect repair operation is undertaken by first～the 5th following defect-restoration method therefor.

In first defect-restoration method therefor, after operation α, proceed following operation β, in this operation β, do not change the irradiation position of laser, come structure 12 irradiations second laser to structure 12 irradiations first laser.At this moment, can use first laser to be defocused so that the laser that the focal position of first laser obtains after away from substrate 11 is used as second laser.

In second defect-restoration method therefor, after operation α, proceed following operation β, in this operation β, change the irradiation position of laser, come structure 12 irradiations second laser to structure 12 irradiations first laser.At this moment, can use with the same laser of first defect-restoration method therefor and be used as second laser.

In the 3rd defect-restoration method therefor, after operation α, proceed following operation β to structure 12 irradiations first laser, in this operation β, do not change the irradiation position of laser, shine second laser, and then the irradiation position of change laser, shine this second laser.At this moment, can use with the same laser of first defect-restoration method therefor and be used as second laser.

In the 4th defect-restoration method therefor, after operation α, proceed following operation β, in this operation β, change the irradiation position of laser, shine three laser different with first laser frequency to structure 12 irradiations first laser.At this moment, the focal position of the 3rd laser defocused in order to than the focal position of first laser more away from substrate 11.

In the 5th defect-restoration method therefor, at structure 12, before irradiation first laser, shine the 4th laser, described the 4th laser is different with the focal position of first laser, and is defocused in order to away from substrate 11, then, after the operation α that carries out structure 12 irradiations first laser, proceed operation β to structure 12 irradiations second laser.At this moment, can use with the same laser of first defect-restoration method therefor and be used as second laser.

Below, each method is described.

[first defect-restoration method therefor]

Fig. 6 A～6D is shown schematically in to form by laser radiation to remove or separate after the repair track R11 in the zone that has fault of construction, removes the figure of an example of the operation of the new fault of construction that is produced on this repair track R11.Structure 12 shown in Fig. 6 A～6D for example is divided into by score line (not shown), and profile is thin OBL a plurality of zoning units.

At first, as shown in Figure 6A, structure 12 is shone the first laser GL1 from substrate 11 sides with pulse type.This first laser GL1 is along the length direction irradiation of thin OBL zoning unit 21.

As the first laser GL1, as long as can remove first conductive layer 13,

photoelectric conversion layer

14 and 15 these the three layers just qualification especially of second conductive layer, for example, can use second harmonic to produce the green laser (green laser) of (SHG, Second Harmonic Generation).As shown in Figure 6A, the focal position F1 of the first laser GL1 is positioned at a face side 11a of substrate 11 and is positioned at position away from structure 12.That is, the first laser GL1 is defocused with respect to structure 12.

In view of the above, shown in Fig. 6 B, can once form repair track R11, described repair track R11 has removed three layers (first conductive layer 13, photoelectric conversion layer 14 and second conductive layers 15) that constitute structure 12.

The SHG laser is for vibrating laser second harmonic (2 times frequency of laser first-harmonic (wavelength 1/2nd)) the laser oscillator of laser beam.The SHG green laser is the laser oscillator of green light as this laser second harmonic that vibrate.As the green laser of this SHG, has CO ₂The second harmonic of laser and YAG laser etc.When using YAG laser, the wavelength of green laser high order harmonic component is 532nm.In addition, can also use the green laser of non-SHG laser to be used as the first laser GL1 certainly.

But, when once removing three layers by said method, a part of 13s of first conductive layer 13 of evaporation as residue attached to the part wall of repair track R11, be on the end 12a of the photoelectric conversion layer 14 and second conductive layer 15, become new fault of construction.

Therefore, shown in Fig. 6 C, on one side the end 12a of the above-mentioned photoelectric conversion layer 14 and second conductive layer 15 is shone the second laser GL2 with pulse type, the length direction along thin OBL zoning unit 21 moves on one side.When carrying out laser radiation, the irradiation position that the irradiation position of the second laser GL2 is compared the first laser GL1 remains unchanged.Can use the first laser GL1 to be defocused so that the laser that the focal position F1 of the first laser GL1 obtains after away from substrate 11 is used as this second laser GL2.That is, the focal position F2 of the second laser GL2 than the focal position F1 of the first laser GL1 more away from substrate 11 (structure 12).The defocus distance difference D1 that represents the difference between the focal position F2 of the focal position F1 of the first laser GL1 and the second laser GL2 for example is 1.0 millimeters (mm).

So, by using the second laser GL2 that obtains after the first laser GL1 defocused, thereby the illuminate condition of the second laser GL2 is changed to the condition that can only remove the photoelectric conversion layer 14 and second conductive layer 15.That is, through among the second laser GL2 that defocuses, shine in the energy of the laser of first conductive layer 13 littler than the energy of the first laser GL1 as mentioned above.Therefore, even shine the second laser GL2, can not remove first conductive layer 13 yet.So, shown in Fig. 6 D, can newly form repair track R12, described repair track R12 has removed the photoelectric conversion layer 14 of a part of 13s of first conductive layer 13 that is attached with evaporation and the end 12a of second conductive layer 15.At this moment, second laser is only removed the photoelectric conversion layer 14 and second conductive layer 15 as mentioned above, therefore can not occur and have the part of the first new conductive layer 13 to be evaporated, and the part of first conductive layer 13 that should evaporate be once more attached to the situation on the repair track R12.

In view of the above, a part of 13s evaporation of first conductive layer 13 be can remove effectively and the photoelectric conversion layer 14 on it and the end 12a of second conductive layer 15 adhered to.Therefore, can be because of a part of 13s of first conductive layer 13 of the end 12a that is attached to the photoelectric conversion layer 14 and second conductive layer 15, and cause first

conductive layer

13 and 15 short circuits of second conductive layer.Consequently can prevent the deterioration of the characteristic of solar cell.

In photoelectric conversion layer 14, include the gas generant matter that produces gases such as hydrogen by laser radiation.Therefore, when and during irradiating laser for a part of 13s of first conductive layer 13 of removing the end 12a that is attached to the photoelectric conversion layer 14 and second conductive layer 15, the energy of this laser is absorbed by photoelectric conversion layer 14, produces gases at high pressure from above-mentioned gas generant matter.By utilizing this higher gas pressure, thereby be accompanied by the removal of photoelectric conversion layer 14, second conductive layer 15 also is removed.

But under the situation of present embodiment, because the second laser GL2 is defocused (the focal position F2 of the second laser GL2 than the focal position F1 of first laser more away from structure 12) more than the first laser GL1, therefore at the peripheral part of laser beam, the energy density of laser descends.Consequently in the end of second conductive layer 15 of repair track R12, the part that might produce second conductive layer 15 is not evaporated and residual so-called burr (burr) 15s.

Therefore, the defect-restoration method therefor that will can not produce burr below describes as second defect-restoration method therefor.

[second defect-restoration method therefor]

Fig. 7 A～7C and Fig. 8 A～8B are shown schematically in to form by laser radiation to remove or separate after the repair track R11 in the zone that has fault of construction, remove the figure of an example of the operation of the new fault of construction that is produced on this repair track R11 by new laser radiation.Structure 12 shown in Fig. 7 A～7C and Fig. 8 A～8B also for example is divided into by score line (not shown), and profile is thin OBL a plurality of zoning units.

At first, shown in Fig. 7 A, structure 12 is shone the first laser GL1 from substrate 11 sides with pulse type.This first laser GL1 is along the length direction irradiation of thin OBL zoning unit 21.

As the first laser GL1,, for example, can use the green laser of SHG (green laser) as long as can remove first conductive layer 13,

photoelectric conversion layer

14 and 15 these the three layers just qualification especially of second conductive layer.Shown in Fig. 7 A, with above-mentioned first defect-restoration method therefor similarly, the first laser GL1 a face 11a side of substrate 11 defocused so that its focal position F1 away from structure 12.In addition, can also use the green laser of non-SHG laser to be used as the first laser GL1 certainly.

In view of the above, shown in Fig. 7 B, can once form repair track R11, described repair track R11 has removed three layers (first conductive layer 13, photoelectric conversion layer 14 and second conductive layers 15) that constitute structure 12.

Therefore, shown in Fig. 7 C, on one side an end 12a of the photoelectric conversion layer 14 and second conductive layer 15 is shone the second laser GL2 with pulse type, the length direction along thin OBL zoning unit 21 moves on one side.At this moment, shown in the solid arrow of Fig. 7 C, move the irradiation position of the second laser GL2, carry out laser radiation along the in-plane of substrate 11.Can use the first laser GL1 to be defocused so that the laser that the focal position F1 of the first laser GL1 obtains after away from substrate 11 is used as this second laser GL2.That is, the focal position F2 of the second laser GL2 than the focal position F1 of the first laser GL1 more away from substrate 11 (structure 12).The defocus distance difference D2 that represents the difference between the focal position F2 of the focal position F1 of the first laser GL1 and the second laser GL2 for example is 1.0mm.

Shown in Fig. 8 A, can form repair track r13 like this, described repair track r13 has only removed among the end 12a of the photoelectric conversion layer 14 of a part of 13s of first conductive layer 13 that is attached with evaporation and second conductive layer 15.

And then, shown in Fig. 8 A, among the same figure shown in the solid line arrow, move the irradiation position of the second laser GL2 along the in-plane (with the rightabout in-plane of Fig. 7 C) of substrate 11, on one side to another end 12a of the photoelectric conversion layer 14 and second conductive layer 15 with the pulse type irradiating laser, on one side move the irradiation position of the second laser GL2 along the length direction of thin OBL zoning unit 21.

In addition, the irradiation of this second laser GL2 can be carried out at the photoelectric conversion layer 14 of the zoning unit that does not have that side of fault of construction and the end 12a of second conductive layer 15 at least.

Shown in Fig. 8 B, can newly form repair track R13 like this, described repair track R13 has also removed another among the end 12a of the photoelectric conversion layer 14 of a part of 13s of first conductive layer 13 that is attached with evaporation and second conductive layer 15.At this moment, with above-mentioned first defect-restoration method therefor similarly, form the condition that the second laser GL2 only removes the photoelectric conversion layer 14 and second conductive layer 15, therefore can not occur and have the part of the first new conductive layer 13 to be evaporated, and the part of first conductive layer 13 that should evaporate be once more attached to the situation on the repair track R13.

In view of the above, the part that can not produce second conductive layer 15 is not evaporated and is remained in so-called burr on the end (end of second conductive layer 15) of repair track, can remove a part of 13s evaporation of first conductive layer 13 more neatly and adheres to the photoelectric conversion layer 14 on it and the end 12a of second conductive layer 15.Therefore, not can because of attached to the part wall of repair track, be a part of 13s of first conductive layer 13 on the end 12a of the photoelectric conversion layer 14 and second conductive layer 15, and cause first

conductive layer

13 and 15 short circuits of second conductive layer.Consequently can prevent the deterioration of characteristic of solar cell.

[the 3rd defect-restoration method therefor]

Fig. 9 A～9C and Figure 10 A～10C are shown schematically in to form by laser radiation to remove or separate after the repair track R11 in the zone that has fault of construction, remove the figure of another example of the operation of the new fault of construction that is produced on this repair track R11 by new laser radiation.Structure 12 shown in Fig. 9 A～9C and Figure 10 A～10C also for example is divided into by score line (not shown), and profile is thin OBL a plurality of zoning units.

At first, shown in Fig. 9 A, structure 12 is shone the first laser GL1 from substrate 11 sides with pulse type.This first laser GL1 is along the length direction irradiation of thin OBL zoning unit 21.

photoelectric conversion layer

14 and 15 these the three layers just qualification especially of second conductive layer.Shown in Fig. 9 A, with above-mentioned first defect-restoration method therefor similarly, the first laser GL1 a face 11a side of substrate 11 defocused so that its focal position F1 away from structure 12.In addition, can also use the green laser of non-SHG laser to be used as the first laser GL1 certainly.

In view of the above, shown in Fig. 9 B, can once form repair track R11, described repair track R11 has removed three layers (first conductive layer 13, photoelectric conversion layer 14, second conductive layers 15) that constitute structure 12.

Therefore, shown in Fig. 9 C, on one side the end 12a of the photoelectric conversion layer 14 and second conductive layer 15 is shone the second laser GL2 with pulse type, the length direction along thin OBL zoning unit 21 moves on one side.When this laser of irradiation, the irradiation position that the irradiation position of the second laser GL2 is compared the first laser GL1 remains unchanged.Can use the first laser GL1 to be defocused so that the laser that the focal position F1 of the first laser GL1 obtains after away from substrate 11 is used as this second laser GL2.That is, the focal position F2 of the second laser GL2 than the focal position F1 of the first laser GL1 more away from substrate 11 (structure 12).The defocus distance difference D3 that represents the difference between the focal position F2 of the focal position F 1 of the first laser GL1 and the second laser GL2 for example is 1.0mm.

Shown in Figure 10 A, by the irradiation of the second laser GL2, can newly form repair track R14, described repair track R14 has removed the photoelectric conversion layer 14 of a part of 13s of first conductive layer 13 that is attached with evaporation and the end 12a of second conductive layer 15.

But a part that produces second conductive layer 15 in the end of second conductive layer 15 is not sometimes evaporated and residual so-called burr 15s.

Therefore, shown in Figure 10 A, continuation is shone the second laser GL2 to an end 12a of the photoelectric conversion layer 14 and second conductive layer 15 with pulse type on one side, along the length direction that approach OBL zoning unit 21 move on one side.When irradiation during this laser, shown in the solid arrow of Figure 10 A, move the irradiation position of the second laser GL2 along the in-plane of substrate 11, carry out laser radiation.

Shown in Figure 10 B, can form repair track r15 like this, described repair track r15 has only removed of end 12a of the photoelectric conversion layer 14 of a part of 13s of first conductive layer 13 that is attached with evaporation and second conductive layer 15.

And then, shown in Figure 10 B, among the same figure shown in the solid line arrow, the irradiation position of the second laser GL2 is moved in continuation along the in-plane (with the rightabout in-plane of Figure 10 A) of substrate 11, on one side to another end 12a of the photoelectric conversion layer 14 and second conductive layer 15 with the pulse type irradiating laser, on one side move the irradiation position of the second laser GL2 along the length direction of thin OBL zoning unit 21.

Shown in Figure 10 C, can newly form repair track R15 like this, described repair track R15 has also removed the photoelectric conversion layer 14 of a part of 13s of first conductive layer 13 that is attached with evaporation and another end 12a of second conductive layer 15.

At this moment, with above-mentioned first and second defect-restoration method therefors similarly, form second laser and only remove the condition of the photoelectric conversion layer 14 and second conductive layer 15, therefore can not occur and have the part of the first new conductive layer 13 to be evaporated, and the part of first conductive layer 13 that should evaporate be once more attached to the situation on the repair track R15.

In view of the above, the part that can remove second conductive layer 15 is not evaporated and is remained in so-called burr on the end (end of second conductive layer 15) of repair track, and can remove a part of 13s evaporation of first conductive layer 13 more neatly and adhere to the photoelectric conversion layer 14 on it and the end 12a of second conductive layer 15.Therefore, not can because of attached to the part wall of repair track, be a part of 13s of first conductive layer 13 on the end 12a of the photoelectric conversion layer 14 and second conductive layer 15, and cause first

conductive layer

[the 4th defect-restoration method therefor]

Figure 11 A～11C and Figure 12 A～12B are shown schematically in to form by laser radiation to remove or separate after the repair track R11 in the zone that has fault of construction, remove the figure of another example of the operation of the new fault of construction that is produced on this repair track R11 by new laser radiation.

Structure 12 shown in Figure 11 A～11C and Figure 12 A～12B also for example is divided into by score line (not shown), and profile is thin OBL a plurality of zoning units.

At first, shown in Figure 11 A, structure 12 is shone the first laser GL1 from substrate 11 sides with pulse type.This first laser GL1 is along the length direction irradiation of thin OBL zoning unit 21.

photoelectric conversion layer

14 and 15 these the three layers just qualification especially of second conductive layer.Shown in Figure 11 A, with above-mentioned first defect-restoration method therefor similarly, the first laser GL1 a face 11a side of substrate 11 defocused so that its focal position F1 away from structure 12.In addition, can also use the green laser of non-SHG laser to be used as the first laser GL1 certainly.

In view of the above, shown in Figure 11 B, can once form repair track R11, described repair track R11 has removed three layers (first conductive layer 13, photoelectric conversion layer 14 and second conductive layers 15) that constitute structure 12.

Therefore, shown in Figure 11 C, on one side an end 12a of the photoelectric conversion layer 14 and second conductive layer 15 is shone the 3rd laser GL3 with pulse type, the length direction along thin OBL zoning unit 21 moves on one side.At this moment, shown in the solid arrow of Figure 11 C, move the irradiation position of the 3rd laser GL3, carry out laser radiation along the in-plane of substrate 11.Can frequency of utilization and first laser GL1 different with the first laser GL1 defocused so that the laser that the focal position F1 of the first laser GL1 obtains after away from substrate 11 is used as the 3rd laser GL3.That is, the focal position F2 of the 3rd laser GL3 than the focal position F1 of the first laser GL1 more away from substrate 11 (structure 12).The defocus distance difference D4 that represents the difference between the focal position F2 of the focal position F1 of the first laser GL1 and the 3rd laser GL3 for example is 1.0mm.

Shown in Figure 12 A, can form repair track r16 like this, described repair track r16 has only removed among the end 12a of the photoelectric conversion layer 14 of a part of 13s of first conductive layer 13 that is attached with evaporation and second conductive layer 15.

As the 3rd laser GL3, for example can be infrared laser (IR, InfraRed laser) (infrared laser).The IR laser is for vibrating ultrared laser oscillator.Infrared ray is the light that wavelength is longer than 780nm, is the big light of heat effect, is also referred to as hot line.As this IR laser, for example can enumerate CO ₂Laser or YAG laser.

When being YAG laser, IR laser is first-harmonic (wavelength 1064nm).

And then, shown in Figure 12 A, among the same figure shown in the solid line arrow, move the irradiation position of the 3rd laser GL3 along the in-plane (direction opposite) of substrate 11 with Figure 11 C, on one side to another end 12a of the photoelectric conversion layer 14 and second conductive layer 15 with the pulse type irradiating laser, on one side move the 3rd laser GL3 along the length direction of thin OBL zoning unit 21.

In addition, the irradiation of the 3rd laser GL3 can be carried out at the photoelectric conversion layer 14 of the zoning unit that does not have that side of fault of construction and the end 12a of second conductive layer 15 at least.

Shown in Figure 12 B, can newly form repair track R16 like this, described repair track R16 has also removed another among the end 12a of the photoelectric conversion layer 14 of a part of 13s of first conductive layer 13 that is attached with evaporation and second conductive layer 15.

At this moment, the 3rd laser GL3 is similarly defocused according to its wavelength and above-mentioned first～the 3rd defect-restoration method therefor, thereby forms the condition of only removing the photoelectric conversion layer 14 and second conductive layer 15.Therefore, can not occur and have the part of the first new conductive layer 13 to be evaporated, and the part of first conductive layer 13 that should evaporate be once more attached to the situation on the repair track R16.

conductive layer

13 and 15 short circuits of second conductive layer, can prevent the deterioration of the characteristic of solar cell.

[the 5th defect-restoration method therefor]

Figure 13 A～13C and Figure 14 A～14C are shown schematically in laser radiation by two stages to form and remove or separate after the repair track R11 in the zone that has fault of construction, remove the figure of an example of the operation of the new fault of construction that is produced on this repair track R11 by new laser radiation.Structure 12 shown in Figure 13 A～13C and Figure 14 A～14C also for example is divided into by score line (not shown), and profile is thin OBL a plurality of zoning units.

At first, as shown in FIG. 13A, structure 12 is shone the 4th laser GL4 from substrate 11 sides with pulse type.The 4th laser GL4 is along the length direction irradiation of thin OBL zoning unit 21.As the 4th laser GL4,, for example, can be the green laser of SHG (green laser) as long as can remove

photoelectric conversion layer

14 and 15 these the two-layer just qualifications especially of second conductive layer.As shown in FIG. 13A, the 4th laser GL4 a face 11a side of substrate 11 defocused so that its focal position F3 away from structure 12.And then, the focal position F3 of the 4th laser GL4 than the focal position F1 of the employed first laser GL1 in the subsequent handling more away from substrate 11 (structure 12).In addition, can also use the green laser of non-SHG laser to be used as the 4th laser GL4 certainly.

In view of the above, shown in Figure 13 B, can form slot part r11, described slot part r11 has removed the photoelectric conversion layer 14 and second conductive layer 15.

Then, shown in Figure 13 B, on one side slot part r11 is shone the first laser GL1 with pulse type, the length direction along thin OBL zoning unit 21 moves on one side.At this moment, the irradiation position of the first laser GL1 irradiation position of comparing the 4th laser GL4 remains unchanged and shines.Can use the 4th laser GL4 to be defocused so that the laser that the focal position F3 of the 4th laser GL4 obtains after near substrate 11 is used as this first laser GL1.That is, the focal position F1 of the first laser GL1 than the focal position F3 of the 4th laser GL4 more near substrate 11 (structure 12).The defocus distance difference D5 that represents the difference between the focal position F3 of the focal position F1 of the first laser GL1 and the 4th laser GL4 for example is 1.0mm.

In view of the above, shown in Figure 13 C, can form repair track R11, described repair track R11 has removed three layers (first conductive layer 13, photoelectric conversion layer 14 and second conductive layers 15) that constitute structure 12.

But, when after the photoelectric conversion layer 14 and second conductive layer 15, removing first conductive layer 13 by said method, a part of 13s of first conductive layer 13 of evaporation as residue attached to the part wall of repair track R11, be on the end 12a of the photoelectric conversion layer 14 and second conductive layer 15, become new fault of construction.

Therefore, shown in Figure 14 A, on one side an end 12a of the above-mentioned photoelectric conversion layer 14 and second conductive layer 15 is shone the second laser GL2 with pulse type, the length direction along thin OBL zoning unit 21 moves on one side.When irradiation during this laser, shown in the solid arrow of Figure 11 A, move the irradiation position of the second laser GL2 along the in-plane of substrate 11, carry out laser radiation.Can use the first laser GL1 to be defocused so that the laser that the focal position F1 of the first laser GL1 obtains after away from substrate 11 is used as this second laser GL2.That is, the focal position F2 of the second laser GL2 than the focal position F1 of the first laser GL1 more away from substrate 11 (structure 12).The defocus distance difference D6 that represents the difference between the focal position F2 of the focal position F1 of the first laser GL1 and the second laser GL2 for example is 1.0mm.

So as shown in Figure 14B, can form repair track r17, described repair track r17 has only removed an end 12a among the end 12a of the photoelectric conversion layer 14 of a part of 13s of first conductive layer 13 that is attached with evaporation and second conductive layer 15.

And then, as shown in Figure 14B, among the same figure shown in the solid line arrow, move the irradiation position of the second laser GL2 along the in-plane (with the rightabout in-plane of Figure 14 A) of substrate 11, on one side to another end 12a of the photoelectric conversion layer 14 and second conductive layer 15 with the pulse type irradiating laser, on one side move along the length direction of thin OBL zoning unit 21.

Shown in Figure 14 C, can newly form repair track R17 like this, described repair track R17 has also removed another among the end 12a of the photoelectric conversion layer 14 of a part of 13s of first conductive layer 13 that is attached with evaporation and second conductive layer 15.

At this moment, with above-mentioned first～the 3rd defect-restoration method therefor similarly, form the condition that the second laser GL2 only removes the photoelectric conversion layer 14 and second conductive layer 15, therefore can not occur and have the part of the first new conductive layer 13 to be evaporated, and the part of first conductive layer 13 that should evaporate be once more attached to the situation on the repair track R17.

conductive layer

Manufacture method according to aforesaid solar cell, when removing or separate the position that produces fault of construction, can not produce new fault of construction, can not be residual this new fault of construction down, and can remove these three layers of first conductive layer, photoelectric conversion layer and second conductive layers, thereby positively make the region insulation that produces fault of construction.Therefore, can not make the deterioration in characteristics in the solar cell, and can repair the position that produces fault of construction.

Symbol description

GL1 first laser

GL2 second laser

GL3 the 3rd laser

GL4 the 4th laser

10 solar cells

11 substrates

Face of 11a

Another face of 11b

12 structures

The 12a end

13 first conductive layers

14 photoelectric conversion layers

15 second conductive layers

The 15s burr

Claims

1. the manufacture method of a solar cell, described solar cell have substrate and on this substrate with the overlapping successively structure that forms of first conductive layer, photoelectric conversion layer and second conductive layer,

This structure is formed a plurality of zoning units by subregion according to each given size on electric, be electrically connected between the described zoning unit adjacent one another are, it is characterized in that the manufacture method of described solar cell comprises:

Defect area is determined operation, determines the zone that has fault of construction from described a plurality of zoning units; And

Reparing process to described zone or its circumfusion laser beam, removes described fault of construction,

Described reparing process comprises:

Operation α shines first laser to described structure, removes or separates described zone; And

Operation β shines second laser to the end of the described structure that produces because of described removal or separation, removes described end,

Described second laser uses and described first laser is defocused so that the laser that the focal position of described first laser obtains after away from described substrate.

2. the manufacture method of solar cell according to claim 1 is characterized in that,

In described operation β, move the irradiation position of described second laser along the in-plane of described substrate, described second laser is shone in the end of the described structure that do not have described that side of fault of construction.

3. the manufacture method of solar cell according to claim 2 is characterized in that,

In described operation β, replace described second laser of irradiation and shine the 3rd laser, the frequency of the laser beam of described the 3rd laser is different with described first laser, and described the 3rd laser defocused so that the focal position of described the 3rd laser than described first laser more away from described substrate.

4. the manufacture method of solar cell according to claim 1 and 2 is characterized in that,

Before described operation α shines described first laser, further have and described structure is shone the 4th laser and form the operation of slot part, described the 4th laser defocused so that the focal position of described the 4th laser than described first laser more away from described substrate,

After forming described slot part, the described slot part of described structure is shone described first laser.